Up to now, anticorrosive plates of metals such as titanium, tantalum, niobium, zirconium and the like having an excellent corrosion resistance have been widely used in various applications, including chemical instruments. Particularly, heavy-gauge anticorrosive metal plate is used in large-size instruments, vacuum instruments and the like.
However, this type of anticorrosive metal is very expensive, so that the instruments using heavy-gauge anticorrosive metal plate are restricted in their use range.
There has been proposed an attempt to reduce the material cost by using a clad steel plate consisting of a steel plate having a certain strength and an anticorrosive metal plate covered thereon, but it is difficult to sufficiently bond the anticorrosive metal plate to the steel plate by the usual method of welding. Therefore, there are often used explosive welded clad plates produced by cladding the anticorrosive metal plate on the steel plate by an explosive welding process using a powder. However, these explosive welded clad plates require a long time for the completion of production, owing to the presence of patent rights and other circumstances. Consequently, the delivery time becomes long. Other disadvantages of the explosive welding process are the facts that the working step is dangerous and the production cost is high, the applicable uses are limited.